[Clinicopathologic features of three cases of erythropoietic protoporphyria with liver involvement]

Objective: To investigate the clinicopathologic features of the erythropoietic protoporphyria (EPP) with liver involvement. Methods: The clinical findings and hepatic biopsy of 3 cases of EPP diagnosed between July, 2011 to August, 2014 with liver involvement were reviewed, with relevant literature review. Results: All patients presented with persistent and refractory abdominal pain, with obvious jaundice and deranged liver function. Imaging showed homogeneous hepatomegaly in all patients. Histologically, the hepatocytes were edematous, and contained numerous cytoplasmic globular brown pigments and bile pigments, which were also found in Kupffer cells, in the bile canaliculi and in some of dilated sinusoid. The pigments were of different sizes and showed uneven distribution. Some pigments showed bright red or yellow birefringence with a distinctive central maltese cross configuration on polarizing microscopy. Furthermore, some hepatocytes showed piecemeal necrosis and steatosis, the portal tracts were usually infiltrated by lymphocytes, with fibroplasia and biliary ductular reaction. There was no dilatation of intrahepatic bile ducts. Conclusion: Full understanding of the clinical and pathological features of EPP with liver involvement can help to recognize this small group of patients, and to offer proper effective treatments.